A turning function based approach for foot outline classification

This study introduces a turning function based technique to classify foot outlines. Foot scans from ten males and ten females were obtained using a laser scanner. The similarities among the different foot shapes were assessed based on the Euclidean distance between turning functions. Thereafter, average linkage clustering was used to classify the differing foot outlines. Two distinct shape groups emerged for both medial and lateral sides. The presence or absence of a medial bulge results in two clusters on the medial side. Similarly, a narrow lateral side with more concavity and a wider lateral side in the midfoot region are the two clusters for the lateral side. More males (60%) showed a bulge on the medial side. The group that belongs to the narrower lateral side were predominantly females (70%). These differences in the structure of the clusters were reflected in the lack of a correlation between the medial and lateral side clusters.